1. Field of the Invention
The invention relates to a receiver and a method of reception in which both an A/D conversion and a phase-split is carried on an input signal to obtain a pair of digital signals which are mutually phase shifted and further processed as a vectorial signal.
2. Description of the Related Art
European Patent Application EP-A 0 486 095 discloses a prior-art receiver of the above-identified type. In the prior-art receiver, a reception signal is first pre-processed by means of analog filters and analog amplifiers. Subsequently, the pre-processed reception signal is subjected to an analog-to-digital (A/D) conversion. A digital filter converts the digitized reception signal into a pair of phase quadrature signals xi and yi. The pair of phase quadrature signals xi and yi is applied to a first Cordic processor which carries out a frequency conversion. As a result, a pair of baseband phase quadrature signals xo and yo is obtained, this pair being low-pass filtered and, subsequently, applied to a second Cordic processor for FM demodulation. For a more comprehensive understanding of the prior-art receiver, reference is made to EP-A 0 486 095 which, in particular, explains the operation of the Cordic processors in great detail.
In EP-A 0 486 095, it is stated that the sampling frequency of the A/D conversion should be at least twice the highest frequency in the radio-frequency (RF) reception range. In a practical embodiment of the prior art receiver with an RF reception range between 87.5 and 108 MHz, the sampling frequency was 350 Mhz.